Fatal cardiac arrest in a calf with uroperitoneum

A five-month-old Belgian Blue female calf presented with a 72-hour history of depression, anorexia, muscle weakness and severe abdominal distension. Abdominal ultrasonography and abdominocentesis revealed the presence of uroperitoneum due to bladder rupture. Venous blood gas analysis showed haemoconcentration, hyperkalaemia and metabolic acidosis. Electrolytes and fluid balance were corrected with aggressive fluid therapy and peritoneal drainage overnight, and surgery was scheduled for the following day. Intraoperatively, gradual drainage of abdominal fluid was performed to avoid sudden haemodynamic changes, and despite successful bladder reconstruction, near the end of surgery, the patient developed severe bradycardia, atrial standstill, sine waves and pulseless electrical activity, unresponsive to cardiopulmonary resuscitation. Cardiac arrest in this calf was likely caused by a combination of washout of toxic product from previous ischaemic tissues, severe acidosis, severe hypoxaemia and electrolyte disturbances. Clinicians should be prepared to handle possible complications of uroperitoneum.